Tachykinin is a generic term for a group of neuropeptides. Substance P (SP), neurokinin A and neurokinin B are known in mammals, and these peptides are known to bind to the corresponding receptors (neurokinin-1, neurokinin-2 and neurokinin-3) that exist in a living body and thereby to exhibit various biological activities.
Of such neuropeptides, SP has the longest history and has been studied in detail. In 1931, the existence of SP in the extract from equine intestines was confirmed, and in 1971, its structure was determined. SP is a peptide consisting of 11 amino acids.
SP is broadly distributed over the central and peripheral nervous systems, and has various physiological activities such as vasodilation, enhancement of vascular extravasation, contraction of smooth muscles, excitation of neurons, salivation, enhancement of diuresis, immunological enhancement and the like, in addition to the function as a transmitter substance for primary sensory neurons. In particular, it is known that SP released from the terminal of the spinal (dorsal) horn due to a pain impulse transmits the information of pain to secondary neurons, and that SP released from the peripheral terminal induces an inflammatory response in the receptor thereof. Thus, it is considered that SP is involved in various disorders (e.g., pain, headache, particularly migraine, Alzheimer's disease, multiple sclerosis, cardiovascular modulation, chronic inflammatory diseases such as chronic rheumatic arthritis, respiratory diseases including asthma or allergic rhinitis, intestinal inflammatory diseases including ulcerative colitis and Crohn's disease, ocular damage and ocular inflammatory diseases, proliferative vitreous retinopathy, irritable bowel syndrome, urinary frequency, psychosis, vomiting, etc.) [see a review article: Physiological Reviews, Vol. 73, pp. 229-308 (1993); Journal of Autonomic Pharmacology, Vol. 13, pp. 23-93 (1993)].
At present, the following compounds have been known as those having antagonistic action for SP receptors.
(1) In EP-A-436,334, disclosed are the compounds of a formula:

(2) in WO 92/17449, disclosed are the compounds of a formula:

(3) in WO 95/16679, disclosed are the compounds of a formula:
and
(4) in JP-A-9-263585, disclosed are the heterocyclic compounds represented by a formula:

wherein Ring M is a heterocycle having —N═C<, —CO—N< or —CS—N< as a partial structure of
Ra and Rb are bonded to each other to form Ring A, or they are the same or different and represent a hydrogen atom or a substituent in Ring M; Ring A and Ring B are optionally substituted homocyclic or heterocyclic rings, respectively and at least one of them is an optionally substituted heterocyclic ring; Ring C is an optionally substituted homocyclic or heterocyclic ring; Ring Z is an optionally substituted nitrogen-containing heterocyclic ring; and n is an integer of 1 to 6, or salts thereof.
An object of the present invention is to provide a piperidine derivative having antagonistic action for a tachykinin receptor, etc. with a different chemical structure from the known compounds including the above-mentioned compounds, a method of preparing the compound, an agent for ameliorating abnormal micturition comprising the compound, and the like.